Activated carbon can be used for adsorption purposes, such as the extraction of gases or vapors from products, for adsorption of liquids and for solvent recovery in various applications. One process used in producing highly active gas adsorbent carbon consists of charring carbonaceous material, such as coconut shells, by application of heat and the further treatment of the carbon so produced with an oxidizing agent such as steam which slowly oxidizes the carbon.
U.S. Pat. No. 1,694,040 discloses a process for making dense strong activated charcoal by impregnating nut cellulose with a dehydrating agent, such as phosphoric acid or zinc chloride, heating the mixture to a temperature not materially below 350.degree. C., leaching out the soluble components and then reheating the resulting carbon in an oxidizing atmosphere.
U.S. Pat. No. 1,819,165 discloses a process for producing highly active gas adsorbent carbon by impregnating carbonaceous material with phosphoric acid, then calcining said impregnated material in the absence of oxygen and then submitting the calcined product to controlled partial oxidation at temperatures above 700.degree. C.
U.S. Pat. No. 3,305,314 discloses a process for producing permanently dehydrated heat treated material from a cellulosic textile material which comprises subjecting the cellulosic material to a controlled partial and selective decomposition of the cellulosic molecule by immersing the cellulosic material in an acid solution to wet the material therewith, removing the wet material from the solution, drying the material to remove the solvent therefrom and heat treating the dried material in an oxidizing atmosphere whereby decomposition involves a rupture of the carbon-oxygen and carbon-hydrogen bonds and the evolution of water, but falling just short of the scission of the main cellulose molecule, through the rupture of the carbon-carbon bonds with the evolution of hydrogen.
Although active carbon has been used extensively in gas and vapor adsorption devices, it is also well suited for the storage of gases such as methane. One of the best active carbons for the storage of methane is derived from chemical activation of coke. These carbons have very high surface areas (2500 to 3000 m.sup.2 /g) and are costly to produce.
It is an object of the present invention to provide a process for producing high surface area activated carbons preferably high surface activated carbons, from inexpensive cellulosic precursors.
It is another object of the present invention to produce activated carbons, preferably high surface area activated carbons, that can be utilized in storage containers to more efficiently store gases such as methane, hydrogen and acetylene.
It is another object of the present invention to provide a process for producing activated carbons, preferably high surface area activated carbons from paper, paper based products and cotton linters.
It is another object of the present invention to provide a process for producing high surface area activated carbon that is cost effective to produce and easy to make.